Wearable absorbent articles (e.g., taped diapers, pull-on diapers, training pants, sanitary napkins, panty liners, incontinence briefs, and bandages) offer the benefit of receiving and containing the bodily exudates of a wearer. Disposable varieties of such absorbent articles are commonly known, and are typically mass produced on a high speed production line. In developed countries such as those in Western Europe and North America, manufacturing line speeds for producing disposable absorbent articles typically exceed 400 products per minute (“PPM”). That is, more than 400 absorbent articles are able to be produced per minute of operation. Packages of absorbent articles sold at retail outlets in developed countries may contain anywhere from more than 10 articles per package to more than 50 articles per package (e.g., 20-count, 40-count or even 160-count). However, less developed countries and countries where the majority of the population has relatively little disposable income, sometimes referred to as “low income markets” or “LIMs”, consumers may not be able to afford to purchase the higher-count packages of disposable absorbent articles, even though such articles may provide superior performance benefits. In order to realize the benefit of superior product performance at a lower cost, consumers in low income markets may choose to use premium disposable absorbent articles or disposable absorbent articles in general less frequently than consumers in higher income markets. For example, instead of applying a disposable diaper to a child multiple times throughout the day, as is often done in higher income markets, consumers in low income markets may use a lower quality disposable diaper or no diaper at all on a child during the day and only put a higher quality disposable diaper on the child at bedtime. In response to this consumer niche, at least some manufacturers of disposable absorbent articles provide low-count packages of disposable absorbent articles (e.g., 10 articles or less) in low income markets, which are more affordable to lower income consumers.
Currently, providing low count packages of disposable absorbent articles such as diapers and training pants is problematic because current manufacturing processes typically run at line speeds which are too fast for packaging low numbers of articles per package. Known processes for packaging stacks of articles typically use an intermittent process. That is, one or more components in the process are required to start and stop in order to provide the desired stack of articles. An example of an intermittent stacking process is disclosed in U.S. Pat. No. 6,089,820. In some known intermittent processes, the stacker, the extractor (i.e., a component that removes articles from the stacker), and/or other process equipment may come to a complete stop in order for articles to be removed from the stacker or moved through the manufacturing process. Once the articles are removed, the stacker and/or extractor restart and accelerate to the desired process speed to process the next stack of articles. While this may be suitable for a high count packaging process, it may not be suitable for low count packaging processes. For example, when going from a 20-count package to a 5-count package, the required number of packages increases by a factor of four for the same number of articles produced. Thus, assuming the rate of article production remains unchanged, the speed of the downstream packaging process must be increased by a factor of four to accommodate the increased number of required packages. In other words, the intermittent components in the process must now stop, start, and accelerate four times as often as before. Such an increase in the starting and stopping of components may cause substantial increased wear on the equipment and require a change in the size of the process equipment or an increase in the size of the motor driving the equipment. Not surprisingly, some manufacturing processes are unable to accommodate the increase in package process speed without undesirably impacting the manufacturing process (e.g., equipment jams/failures, package miscounts, process slow-downs). Because there is a demand in low income markets for a manufacturer's product, the manufacturer may, at least in some instances, resort to manually packaging articles. However, packaging articles by hand is generally slower and more labor intensive than an automated process, and may result in an undesirable increase in workforce or reduction in capacity (i.e., fewer packages of articles).
While some attempts to provide a process for making low-count packages of disposable absorbent articles have been made, such attempts have only resulted the undesirable slow down of portions of the manufacturing process (e.g., through the use of vertically oriented screw stackers such as are disclosed in U.S. Pat. Nos. 6,089,820 and 6,149,378) or the undesirable use of space-consuming equipment (e.g., horizontally oriented stackers such as are disclosed in U.S. Pat. No. 6,698,579). Efforts to provide low-count packages of articles such as, for example, disposable diapers have resulted in undesirable impacts to the manufacturing process, increased product defects, rejections, and overall waste.
Accordingly, it would be desirable to provide a suitable process for making low-count packages of articles at high speeds. It would also be desirable to provide a continuous process for making low-count packages of articles at high speeds. It would also be desirable to provide such a process without the need for space-consuming equipment.